Refer to FIG. 1 showing a schematic diagram of a SIM card control apparatus controlling a SIM card. Generally, a mobile phone uses a SIM card control apparatus 122 to control a SIM card 20. In a mobile phone communication system, such as a Global System for Mobile communications (GSM) system, phone number information of the mobile phone is recorded in the SIM card, which is given to a subscriber by a mobile phone service provider. When the SIM card is plugged into a SIM card slot of the mobile phone and the mobile phone is powered on, the SIM card control apparatus 122 activates the SIM card 20 to enable the mobile phone to hook onto the mobile network service.
As mobile phones prevail, more and more people have two or even several mobile phone numbers. Each of the numbers has a corresponding SIM card and usually one mobile phone accommodates only one SIM card. Therefore, people having several phone numbers have to simultaneously carry several mobile phones to receive phone calls or messages of the phone numbers. In order to solve the problem that a user has to carry several mobile phones, a mobile phone capable of accommodating two SIM cards while maintaining both of the different phone numbers in the standby mode has become available to the market.
Refer to FIG. 2 showing a schematic diagram of using two SIM card controllers to control two SIM cards in the prior art. A conventional mobile phone capable of accommodating two SIM cards has a SIM card controller 122 and a SIM card controller 124, which are used for controlling a SIM card 20 and a SIM card 30 respectively, so as to receive phone calls or messages of the two phone numbers. However, this method can only be implemented by applying two SIM card controllers to a dual-card mobile phone, and hence production cost of the mobile phone is increased.